Variable resistance exercising device

ABSTRACT

Disclosed is an exercising device in which stacked weights are manipulated by the user through a lever arm. A selected quantity of weights is raised and lowered on vertical guide rods by a lift rod. The lever arm is pivoted to the frame of the device and passes through a yoke in the upper end of the lift rod. A roller mounted in the yoke is carried on the upper surface of the lever arm. The lever arm is substantially horizontal when the device is at rest and as the lever arm is raised, the roller on the lift rod moves on the lever arm to reduce the user&#39;s mechanical advantage and increase his effective load. Also, as the lever arm is raised through its pivotal arc, a vectoring of the lifting force occurs, varying the portion of that force which is devoted to lifting of the weights, and thereby further increasing the effective load on the user. Further variations in resistance are possible by contouring the upper surface of the lever arm or the roller.

BACKGROUND OF INVENTION

This invention relates generally to exercise devices and moreparticularly to devices which provide a variable amount of resistance tothe user during an exercise movement.

According to current concepts, muscle development is best achieved byexercises which are carried out in such a manner that the muscles arecontinuously worked at a level of nearly maximum effort during theexercise.

Most currently known exercise devices are not capable of providing thistype of exercise because the resistance which they exert remainsconstant or decreases throughout the exercise movement while thestrength exertable by the user's muscles varies at different points inthe movement, and generally increases where the machine resistancedecreases. Therefore, a degree of resistance which, at one point in anexercise movement may require near maximum effort to overcome, will atsome other point in the movement be either too much or too little.

It has, therefore, been a desire of both exercisers and coaches to havean exercise device which can vary the applied resistance during anexercise movement to correspond with variations in available musclestrength. Attempts have been made to satisfy this desire, however, theresultant devices have been excessively complex and expensive.

It is, therefore, a major object of my invention to provide an exercisedevice in which the resistance varies as the user moves the devicethrough the exercise cycle.

It is also an object of my invention to provide an exercise device ofthe type described in which the manner of variation of the resistanceduring the exercise cycle is adjustable.

It is another object of my invention to provide an exercise device ofthe type described in which the variation of resistance occurs becauseof changes in the length of a lever arm through which the resistance isapplied.

It is a further object of my invention to provide an exercise device ofthe type described in which the resistance is varied by the vectoring ofthe force applied to the machine by the user during the exercise cycle.

Still another object of my invention is to provide an exercise devicestructured to readily withstand heavy forces and extensive use.

Still a further object of my invention is to provide an exercise deviceof the type described in which the resistance varying mechanism can beincorporated into many types of existing exercise devices withoutsubstantially increasing their cost.

Yet another object of my invention is to provide an exercise device ofthe type described which is relatively inexpensive to manufacture,simple to use and substantially maintenance free.

DESCRIPTION OF DRAWINGS

These and other objects and advantages of my invention will become morereadily apparent from the following detailed description of a preferredembodiment and the accompanying drawings in which:

FIG. 1 is an elevational section view of a first preferred embodiment ofmy invention with movement in the exercise cycle shown in phantom;

FIG. 2 is a sectional view taken on 2--2 in FIG. 1;

FIG. 3 is a front elevational view of the preferred embodiment of FIG.1;

FIG. 4 is an enlarged perspective view of the movable connection whichchanges the lever advantage during the exercise cycle;

FIG. 5 is an elevational section view of a second preferred embodimentof my invention;

FIG. 6 is a partial sectional view taken at 6--6 in FIG. 5;

FIG. 7 is a sectional view taken at 7--7 in FIG. 6;

FIG. 8 is a partial sectional view taken at 8--8 in FIG. 5.

FIG. 9 is an enlarged partial side elevational view of my secondpreferred embodiment showing the first form of a modification forprogrammed resistance; and

FIG. 10 is an enlarged partial side elevational view of my secondpreferred embodiment showing a second form of a modification forprogrammed resistance.

DETAILED DESCRIPTION OF PARTS

Referring now to the drawings, and particularly FIGS. 1 through 4thereof, my muscle building exercise device 10 has a floor mountedupstanding frame 12. The frame 12 contains a stack of weights 14 mountedon a pair of guide rods 16. The guide rods 16 are pivotally attached tothe lower portion of the frame by pivot connections 18 so that as theweights are lifted the guide rods 16 can pivot inwardly or outwardly ofthe frame on either side of true vertical to adjust to the path of theweights. The weights 14 have bushed guide holes 20 which travel on theguide rods 16. The weights 14 also have centerholes 22 through which aweight lift rod 24 passes. The number of weights to be lifted areselected by inserting a selector pin 26 through pin holes 28 in theweight lift rod 24 below the bottom weight of the stack selected.

A lever arm 30 is pivotally mounted in the frame 12 on the side oppositethe weights 14 by a mounting shaft 32. The lever arm 30 has a handleportion 33 which extends through the frame 12 above the weights 14 andoutwardly beyond the frame on the side where the weights are located.Handle bars 34 are provided on its distal end.

The lever arm 30 also has a foot portion 36 connected to the handleportion 33 at the mounting shaft 32 and extending downward and outwardfrom the mounting shaft on the same side of said frame 12 at an obtuseangle to the handle portion. At its distal end the foot portion 36 has apedal plate 38 disposed for contact by a user's feet.

Still other means for moving the lever arm 30 are provided by a pullcable 40 attached to the handle portion 33 by a selected one of a pairof the ears 42. The cable 40 extends upwardly in the frame 12, over apair of sheaves 44 on the top of the frame, and down to a pull handle46.

To attach the weight lift rod 24 to the lever arm 30, a yoke 48 issecured to the top of the lift rod and extends upwardly on either sideof the lever arm (see FIG. 4). A roller 50 is mounted between the legs52 of the yoke 48 and disposed to travel longitudinally along the uppersurface 54 of the lever arm 30. The pivotal mounting of the lever arm 30is so located that the upper surface 54 is disposed in a generallyhorizontal position when the lifting pressure is first applied to theweight lift rod 24 through the yoke 48. As the user forces the handlebars 34 upward the lever arm 30 pivots about the mounting shaft 32 onthe opposite side of the frame 12 and the upper surface 54 becomesinclined toward the pivot point. As this inclining of the upper surface54 occurs, the roller 50 on the upper end of the weight lift bar 24tends to move toward the pivot point and pivot the guide rods 16inwardly in the frame 12.

To control the position of the guide rods 16 and the upper end of theweight lift rod 24, a guide arm 56 is connected between the yoke 48 andthe opposite side of frame 12. The guide arm 56 has one end pivotallymounted on a guide arm shaft 58 in the frame 12 and the other endpivotally mounted between the legs 52 of the yoke 48 by mounting pin 60.

The guide arm shaft 58 is mounted on the same side of frame 12 as thelever arm mounting shaft 32, by movable mountings 62. These movablemountings 62 are adjustable to vary the distance between the guide armshaft 58 and the mounting shaft 32 which pivotally mounts the lever arm30. Also, the guide arm 56 is formed of two telescopically connectedsections 64 which are releasably secured by adjustment holes 66 and anadjustment pin 68. By these means, the guide arm 56 is made adjustablein length and point of pivoting.

Since the guide arm 56 controls the position of the upper end of theweight lift rod 24, it will be understood that with the guide arm shaft58 positioned as shown in FIG. 1 and the guide arm 56 adjusted at thelength shown in FIG. 1, raising the handle portion 33 of lever arm 30will cause the upper end of the weight lift rod 24 to follow an arcuatepath as shown by dotted line 70. During this travel, the roller 50 willmove outwardly on the upper surface 54 of the lever arm 30 away from themounting shaft 32 thereby reducing the mechanical advantage available tothe user at the handle bars 34 in lifting the weights 14. The guide rodswill first pivot outwardly and then inwardly in the frame 12 about thepivot connections 18 to adjust to the path of the weights.

Since the lever arm 30 and the guide arm 56 in the arrangement of FIG. 1are so interrelated that they serve as opposite legs of a parellogram asthe lever arm 30 passes through its lifting movement, it will beunderstood that the distance which the roller 50 will travel outward onthe upper surface 54 of the lever arm 30 at any particular point in themovement, and the rate of that travel, will be determined by thedistance between the mounting shaft 32 and the guide arm shaft 58, andthe length of the guide arm 56. Since these factors can be varied bychanging the length of guide arm 56 using adjustment holes 66 andadjustment pin 68, and by changing the distance between the guide armshaft 68 and mounting shaft 32 by using the movable mountings 62, thelocation and rate of change of the variations in resistance experiencedby the user at particular points in the exercise movement areadjustable. Furthermore, adjustment of the length and pivot point of theguide arm 56 will change the manner in which the force vectoring occurs,thereby modifying the resistance variations brought about by the leverarm changes.

The change in mechanical advantage is brought about, of course, bymovement of the roller 50 during the exercise movement outwardly alongthe upper surface 54 of the lever arm 30 to positions more distant fromthe pivot point of the lever arm at the mounting shaft 32 than theposition in which the roller 50 was located when the exercise cyclebegan, and is further affected by the force vectoring.

In FIG. 1 I have illustrated the vectoring of forces which occur duringthe exercise movement. The letter W represents the weight vector whichresolves itself, at the position shown in phantom, into axial weightvector W₁, directed toward the pivot point of lever arm 30, and momentweight vector W₂, directed against the pivotal movement urged by theuser. Since the guide arm 56 resists the force of axial weight vector W₁and prevents movement of the roller 52 toward the mounting shaft 32, itmust supply an equal and opposite resistance vector R₁. Since the guidearm 56 can only apply resistance force axially along the guide arm,however, the R₁ vector must be derived from a guide arm resistance forcevector R. This results in a moment resistance vector R₂ being applied bythe guide arm 56 which combines with the moment weight vector W₂ toincrease the resultant moment resistance applied against the pivotalmovement urged by the user. Since the moment weight vector W₂ is reducedas the lever arm 30 is pivoted upwardly, this must be overcome bychanges in the lever arm and an increase of the R₂ moment resistancevector in order for the user to meet with an increasing effectiveresistance during the upward movement of the lever arm. At the pointshown in phantom in FIG. 1 it will be seen that the addition of theweight moment vector W₂ and the resistance moment vector R₂ still do notequal the main weight vector W. The lever arm increase more thancompensates for this reduction of the effective moment force, however,so the user experiences more resistance at this point than at thestaring point of the exercise where the lever arm 30 is substantiallyhorizontal. At other points in the exercise movement the addition of theW₂ and R₂ vectors will exceed the main weight vector W and will,therefore, combine with the lever arm change to further increase theresistance experienced by the user. The reduction in the W₂ vectorduring the exercise movement illustrates the fault in presently knownexercise devices which use a pivoted lever arm similar to thisembodiment. As the lever arm moves closer to vertical more and more ofthe weight is supported by the pivot and the effective resistance to theuser is reduced. Generally this occurs where the user's muscle strengthis increasing, so full muscle development is not achieved. My deviceovercomes this disadvantage, as explained.

It will also be understood that the same effect with respect tovariation of the user's mechanical advantage and vectoring of theresultant forces will be achieved by moving the lever arm 30 by means ofthe foot portion 36 through foot pedal plate 38 or by the cable 40through handle 46.

OPERATION OF FIRST EMBODIMENT

Having described the structural details of the first preferredembodiment of my exercising device, I will now describe its operation.

The operation will be explained in conjunction with the practice ofexercises typically used in machines of this type. One such exercise isa bench press. In this technique the exerciser lies on his back on abench with his head toward the exercising device and grips the handlebars 34 with his hands. The height of the bench is such that his armsare well retracted with his hands located near his chest when theexercise is started. Starting with the handle bars 34 just above him theuser then extends his arms and presses the handle bars 34 upward untilhis arms reach their fully extended position above him. Then he slowlyretracts his arms again lowering the handle bars 34 to their originalposition.

The user will normally select, for this exercise, the maximum weightwhich he is able to lift when his arms are in retracted position. Havingselected these weights by placing the pin 26 in the proper hole 28 ofthe weight lift rod 24, the user then presses upwardly on the handlebars 34. As the handle bar 34 is forced upward, the weights 14 arecarried upward by the weight lift rod 24 because of the engagement ofthe roller 50 with the upper surface 54 of the lever arm 30.

The more the lever arm 30 is driven up, the further roller 50 is movedaway from the mounting shaft 32 about which the lever arm 30 pivots.This, of course, moves the lifting point of the weights closer to thehandle bars 34 as the lever arm 30 is forced upwardly, and the user isthus subjected to a decreasing mechanical advantage and a greaterresistance from the same amount of weight. When the user lowers thehandle bars 34, the opposite movement of roller 50 occurs and thestrength required to support the weight stack as the arms are retractedbecomes less.

At the same time the vectoring of the weight force W into a reducing W₂weight moment vector is at least partially overcome, and at some pointsis more than overcome, by the movement resistance vector R₂, thusfurther enhancing the increase in resistance experienced by the user.Since neither the lever arm change nor the force vectoring change inthis embodiment is linear, the resistance changes experienced by theuser are non-linear during the exercise movement, and as explained, willvary depending on the guide arm pivot location and length.

It will be understood by those skilled in the art that the variation ofresistance during the exercise movement of this exercise does notexactly correspond with the available muscle strength of the user atvarious points in the movement. A closer correspondence may be achieved,however, by contour adaptions to the upper surface 54 of the lever arm30 or the periphery of the roller 50, as will be explained later.

SECOND EMBODIMENT

In FIGS. 5 through 8 I show a modified form of my invention representedgenerally by the numeral 80. The modified form has a frame 82substantially identical to the frame 12 in my first embodiment whichcarries weight 84 on one side. The weights 84 are mounted on guide rods86 in the same manner as in my first embodiment except that in thisembodiment the guide rods are not pivotally mounted to the frame but arerigidly affixed thereto at top and bottom. The weights 84 have bushedguide holes 88 which travel on the guide rods 86, in the same manner asin my first embodiment. The weights 84 are engaged and lifted by aweight lift rod 90 which passes through center holes 92 in the center ofthe weights in the same manner as in my first embodiment, and the numberof weights selected is regulated by inserting a pin 94 into pin holes 96in the weight lift rod.

The second embodiment of my invention also has a lever arm 100 pivotallymounted in the frame 82 on a mounting shaft 102 disposed on the oppositeside of the frame from the weights 84. The lever arm 100 has a handleportion 104 which extends across the frame from the mounting shaft 102,over the weights 84 and outside the frame 12, and has handle bars 106mounted on its distal end. A yoke 108 is attached to the upper end ofthe weight lift rod 90 and extends upward about each side of the leverarm 100. A main roller 110 is mounted between the upstanding legs 112 ofthe yoke 108 and disposed to roll on the upper surface 114 of the leverarm.

In this second embodiment, moving the lever arm 100 upwardly about itspivot point at the mounting shaft 102 by applying upward pressure to thehandle will not only carry the weights 84 up the guide rods 86 but willforce them against the rods as the lever arm moves through its arcuatepath. The weights 84 are forced against the guide rods by reason of thetendency of the main roller 110 to travel toward the mounting shaft 102on the upper surface 114 of the lever arm 100 when the lever arm israised to incline the upper surface toward the mounting shaft. Toprevent excessive wear on the guide rods 86 and the guide holes 88 ofthe weights 84, a pair of alignment rollers 116 is provided on the yoke108 on each side of the main roller 110. The alignment rollers 116travel on the guide rods 86 and hold the weight lift rod 90 in verticalalignment with the guide rods. This action of the alignment rollers 116holds the stack of weights centered on the guide rods 86 and preventsexcessive wear on one side of the bushed guide holes 88.

To accommodate the main roller 110 and the alignment rollers 116, thelegs 112 of yoke 108 extend outwardly from the guide rods 86 and mount aroller shaft 118 therebetween which carries the rollers. Spacers 120 areprovided between the legs 112 and the alignment rollers 116 to hold thealignment rollers in alignment with the guide rods 86.

In this second embodiment, as in the first, the main roller 110 iscaused to move outward on the upper surface 114 of the lever arm 100 asthe handle portion 104 is raised by the handle bars 106 in the exercisemovement. This movement of the main roller 110 reduces the mechanicaladvantage to the user, in the same manner as in my first embodiment,however, the amount and rate of change will not be the same as in myfirst embodiment.

Vectoring of the forces will occur in this embodiment, in a mannergenerally similar to that described in my first embodiment, and thisvectoring is indicated by the vector diagram in FIG. 5. Again, W is theweight resistance vector which resolves itself into an axial weightvector W₁, and a moment weight vector W₂. Movement toward the pivotpoint by the roller 110 is prevented by vector R₁, which results fromthe vectoring of the main resistance vector R applied by the guide rods86 through the alignment rollers 116. When the main resistance vector Rdivides to provide the axial resistance vector R₁ equal and opposite toweight axial vector W, a resistance moment vector R₂ results. Momentvectors W₂ and R₂ combine into a moment resistance which resists thepivotal movement being urged by the user.

OPERATION OF SECOND EMBODIMENT

The operation of my second preferred embodiment is substantially thesame as for my first embodiment, except that the proportionate change ofmechanical advantage as the lever arm 100 moves through its cycle issomewhat different. This is due to the direct vertical path of travel ofthe yoke 108 along the guide rods 86. My second embodiment, of course,does not provide means for changing the lever advantage conditions as inmy first embodiment where this is accomplished by the adjustable lengthand pivot point of the guide arm 64.

In this embodiment, as the handle bars 106 are raised, the weight liftrod 90 is raised by engagement with the main roller 110 on the uppersurface 114 of the lever arm 100. Since the alignment rollers 116 travelupward on the guide rods 86, the main roller 110 is drawn outwardlyalong the upper surface 114 as the lever arm 110 continues to moveupwardly. This, together with the vectoring described, reduces themechanical advantage to the user, and requires him to exert more forceto lift the same weight. When the handle bars 106 are lowered again themain roller 110 moves inward on the lever arm 100, returning the lostmechanical advantage to the user.

PROGRAMMED RESISTANCE MODIFICATIONS

From this description of the structure and operation of preferredembodiment it will be understood that my exercise device can readilyfulfill the desire for a machine with a resistance which varies duringthe exercise movement.

I will now describe further modifications of my invention which can beutilized to more closely match the resistance at any point in theexercise movement to the user's potential muscle strength at that point.

Actually, in performing a bench press, for example, the user's potentialmuscle strength is relatively high at the beginning of the exercisemovement where his arms are fully retracted and highest at the end ofthe movement as his arms reach full extension. About midway through theexercise movement, however, there is a weak point in muscle strengthpotential. This occurs about the position where the upper and lower armform a right angle at the elbow. In weight lifting exercises this pointis sometimes referred to as a sticky spot.

In FIGS. 9 and 10 I show modifications in my second embodiment whichadapt my device to the muscle strength positions in a bench pressexercise movement. Referring to FIG. 9, the numeral 120 designates aguide block with a contoured upper face 122. The guide block 120 issecured to the upper surface 114 of the lever arm 100 in the area oftravel of the roller 110 by attachment bolts 124. As the roller 110moves away from the pivot point of the lever arm 100 it is caused firstto travel upwardly at a more rapid rate than would normally occur whenit travels on the flat upper surface 114 of the lever arm. Then theroller passes into a back-off point on the contoured surface where theupward travel is virtually halted, and, finally, the roller commencesfurther upward travel ar an accelerated rate as it moves outward overthe last portion of the guide block 120.

In FIG. 10 I accomplish a similar result using a contoured roller 126and a rack gear 128. The rack gear 128 is secured to the upper surface114 of the lever arm 100 by attachment bolts 130. The contoured roller126 has peripheral teeth 132 which engage the rack gear 128 and preventany skidding of the roller during movement along the lever arm. Thecontour roller 126 is interchangeable with rollers of other contours.

With either of these modifications it will be understood that bychanging the guide block 120 or the contoured roller 126 I can adapt mydevice to provide nearly any desired variation of resistance in anexercise cycle.

In utilizing these modifications it should be understood that thevariations of resistance experienced by the user are as much andpossibly more, the result of changes in the manner that the forces arevectored as they are the result of changes in the lever arm length.Changes in the force vectoring occur by reason of the different angle ofincidence between the roller 110 and the lever arm 100 due to thecontoured surface 122 on the guide block 120, or between the contouredroller 126 and the rack gear 128 (see FIGS. 9 and 10).

Because of the simplicity of structure by which my inventionaccomplishes the desired variation in resistance, there are numerousother modifications which could be easily incorporated. The pivot pointof the lever arm could be made movable with respect to the frame tomodify the manner in which the mechanical advantage is changed duringexercise movement, and a suitable mechanism could be employed to varythe lever arm length during an exercise movement by moving the lever armwith respect to the pivot point rather than with respect to the point atwhich the weights are connected.

Also, of course, resistance may be provided by means other than weights,and still be made fully compatible with my device.

From this description it should be understood that I have provided anexercise device fully capable of attaining the objects and providing theadvantages heretofore granted it. It should also be understood that thevariable resistance provided by my device is adaptable to my differenttypes of exercise devices. By arranging the change of lever advantage toprovide greater resistance at those my in the exercise cycle where theuser has the greatest available strength, maximum muscle development canbe achieved with my device.

Finally, it will be understood that my exercise device can beinexpensively made, and even combined into existing equipment, and issimple to use.

I claim: .[.1. An exercise device comprising: An exercise device .[.asdescribed in claim 2, in which.]. .Iadd.comprising.Iaddend.:.Iadd.aframe; a lever arm pivotally mounted in said frame at a lever arm pivotand pivotally movable by a user through an exercise cycle; user contactmeans interconnected with said lever arm for applying pivotal movementforce thereto; resistance means interconnected with said frame; and aninterconnection mechanism interconnecting said resistance means to saidlever arm at a lever arm connecting point disposed in spaced relationwith said lever arm pivot, said interconnection mechanism havingmovement means movable in response to pivotal movement of said lever armto vary the spaced relationship between said lever arm connecting pointand said lever arm pivot; wherein said interconnection mechanismmovement means includes a yoke connected to said resistance means anddisposed about a portion of said lever arm, and a yoke rollerinterconnected with said yoke and disposed to travel longitudinallyalong said lever arm during pivotal movement thereof; guide meansinterconnected with said frame and disposed to direct the path ofmovement of said movement means; and wherein .Iaddend. said lever armhas a non-linear contoured surface path; and said roller of saidinterconnection mechanism travels along said path on said lever arm. 4.An exercise device .[.as described in claim 2 in which.]..Iadd.comprising.Iaddend.:.Iadd.a frame; a lever arm pivotally mountedin said frame at a lever arm pivot and pivotally movable by a userthrough an exercise cycle; user contact means interconnected with saidlever arm for applying pivotal movement force thereto; resistance meansinterconnected with said frame; and an interconnection mechanisminterconnecting said resistance means to said lever arm at a lever armconnecting point disposed in spaced relation with said lever arm pivot,said interconnection mechanism having movement means movable in responseto pivotal movement of said lever arm to vary the spaced relationshipbetween said lever arm connecting point and said lever arm pivot;wherein said interconnection mechanism movement means includes a yokeconnected to said resistance means and disposed about a portion of saidlever arm, and a yoke roller interconnected with said yoke and disposedto travel longitudinally along said lever arm during pivotal movementthereof; guide means interconnected with said frame and disposed todirect the path of movement of said movement means; and wherein.Iaddend. said roller of said interconnection mechanism has anon-circular contoured periphery with gear teeth and said lever arm hasa substantially linear rack gear engageable by said roller teeth.
 5. Anexercise device .[.as described in claim 1, in which.]..Iadd.comprising.Iaddend.:.Iadd.a frame; a lever arm pivotally mounted in said frame ata lever arm pivot and pivotally movable by a user through an exercisecycle; user contact means interconnected with said lever arm at alocation remote from and in fixed relationship to the lever arm pivotfor applying pivotal movement force thereto; resistance meansinterconnected with said frame; and an interconnection mechanisminterconnecting said resistance means to said lever arm at a lever armconnecting point disposed in spaced relationship with said lever armpivot, said interconnection mechanism having movement means movable inresponse to pivotal movement of said lever arm to vary the spacedrelationship between said lever arm connecting point and said lever armpivot, and guide means interconnected with said frame and disposed todirect the path of movement of said movement means; .Iaddend. saidinterconnection mechanism guide means .[.define.]. .Iadd.defining.Iaddend.a substantially linear path disposed in intersectingrelationship with the longitudinal axis of said lever arm at allpositions of said lever arm during its pivotal movement through saidexercise cycle, and engageable by said movement means to guide saidlever arm connecting point along a predetermined path during movement ofsaid lever arm.
 6. An exercise device as described in claim 5, inwhich:said guide means of said interconnection mechanism includes a pairof upstanding rods mounted in said frame, one on each side of said leverarm and a pair of alignment rollers interconnected with said movementmeans of said interconnection mechanism and disposed to travel alongsaid rods.
 7. An exercise device .[.as described in claim 5, in which.]..Iadd.comprising.Iaddend.: .Iadd.a frame; a lever arm pivotally mountedin said frame at a lever arm pivot and pivotally movable by a userthrough an exercise cycle; user contact means interconnected with saidlever arm for applying pivotal movement force thereto; resistance meansinterconnected with said frame; and an interconnection mechanisminterconnecting said resistance means to said lever arm at a lever armconnecting point disposed in spaced relationship with said lever armpivot, said interconnection mechanism having movement means movable inresponse to pivotal movement of said lever arm to vary the spacedrelationship between said lever arm connecting point and said lever armpivot, and guide means interconnected with said frame and disposed todirect the path of movement of said movement means; said interconnectionmechanism guide means defining a substantially linear path disposed inintersecting relationship with the longitudinal axis of said lever armat all positions of said lever arm during its pivotal movement throughsaid exercise cycle, and engageable by said movement means to guide saidlever arm connecting point along a predetermined path during movement ofsaid lever arm; and wherein .Iaddend. said guide means of saidinterconnection mechanism includes a guide arm having a proximal endpivotally mounted to said frame in spaced relationship with said leverarm pivot and a distal end interconnected with said movement means ofsaid interconnection mechanism.
 8. An exercise device .[.as described inclaim 1, in which:.]..Iadd.comprising a frame;a lever arm pivotallymounted in said frame at a lever arm pivot and pivotally movable by auser through an exercise cycle; user contact means interconnected withsaid lever arm at a location remote from and in fixed relationshiprelative to the lever arm pivot for applying pivotal movement forcethereto; resistance means interconnected with said frame; and aninterconnection mechanism interconnecting said resistance means to saidlever arm at a lever arm connecting point disposed in spacedrelationship with said lever arm pivot, said interconnection mechanismhaving movement means movable in response to pivotal movement of saidlever arm to vary the spaced relationship between said lever armconnecting point and said lever arm pivot, and guide meansinterconnected with said frame and disposed to direct the path ofmovement of said movement means; .Iaddend. said interconnectionmechanism movement means .[.includes.]. .Iadd.including .Iaddend.rollermeans interconnected with said resistance means and disposed to movelongitudinally with respect to said lever arm upon pivotal movement ofsaid lever arm to vary the spaced relationship between said lever armconnecting point and said lever arm pivot; and said interconnectionmechanism guide means .[.includes.]. .Iadd.including .Iaddend.a rigidmember interconnected with said frame and said roller means and disposedto guide said roller means along a predetermined path during movement ofsaid lever arm through said exercise cycle.
 9. An exercise devicecomprising:a frame; resistance means mounted to said frame; a lever armmounted in said frame .Iadd.and movable about a pivot axis fixedrelative to the lever arm and the frame.Iaddend.; user contact meansinterconnected with said lever arm and disposed to move said lever armin said frame; coupling means interconnecting said resistance means andsaid lever arm, said coupling means includes movement means movable inresponse to movement of said lever arm to vary the point ofinterconnection between said resistance means and said lever arm; andguide means interconnected with said frame and disposed to engage andguide the movement of said coupling means along a path adapted to varythe manner in which said resistance of said resistance means is leveredand vectored to resist movement of said lever arm.
 10. An exercisedevice as described in claim 9 in which:said resistance means includes astack of weights mounted in said frame and vertically movable withrespect thereto; and said coupling means includes a vertically disposedrod having a lower end interconnected with said weights and having aroller mounted on the upper end thereof, said roller being disposed totravel longitudinally along said lever arm as said lever arm .Iadd.ismoved .Iaddend.with respect to said frame.
 11. An exercise device asdescribed in claim 10 in which:said lever arm is pivotally mounted insaid frame; and said user contact means is disposed to permit pivotalmovement of said lever arm.
 12. An exercise device as described in claim11, in which:said guide means includes a rigid member defining asubstantially linear path disposed for engagement by said coupling meansto vary the distance between said lever arm pivot point and the point ofinterconnection between said resistance means and said lever arm duringmovement of said lever arm with respect to said frame. .Iadd.
 13. Anexercise device comprising: a frame; a lever arm pivotally mounted inthe frame at a lever arm pivot and pivotally movable by a user throughan exercise cycle; user contact means attached to an end of the leverarm remote from and in fixed relationship relative to the pivot forapplying a pivotal movement force to the lever arm during an exercisecycle; resistance means interconnected with the frame; and aninterconnection mechanism interconnecting the resistance means to thelever arm at a lever arm connecting point located in spaced relationshipwith the lever arm pivot, the interconnection mechanism having movementmeans movable in response to pivotal movement of the lever arm to varythe spacing along the lever arm between the lever arm connecting pointand the pivot, and guide means interconnected with the frame anddisposed to direct the path of movement of the movement means..Iaddend..Iadd.
 14. An exercise device comprising a frame; a lever arm pivotallymounted in the frame for pivotal motion about a pivot axis on the frameduring an exercise cycle, the lever arm including user contact means ata point remote from and in fixed relationship relative to the pivotaxis; resistance means attached to the frame; and an interconnectionmechanism connected with the resistance means and the lever arm forapplying a force generated by the resistance means to the lever arm at alever arm force applying point intermediate the user contact means andthe pivot axis; movement means inducing relative movement between themechanism and the lever arm over a portion of the length of the latterwhen the lever arm is pivoted through an exercise cycle to vary thepoint of interconnection between the resistance means and the lever arm,so that during an exercise cycle the effective moment arms of theresistance means and the user contact means about the pivot axis varyduring an exercise cycle; and guide means interconnected with the frameand disposed to direct the path of movement of the movement means;whereby the force that must be applied by a user to the user contactmeans to move the lever arm in opposition to the resistance means variesover the course of the exercise cycle. .Iaddend. .Iadd.
 15. An exercisedevice comprising a frame; a lever arm mounted in the frame for movementabout a pivot axis fixed relative to the frame and the lever arm, thelever arm including handle means spaced from the pivot axis for applyinga force to the lever arm for pivotally moving the lever arm about theaxis through an exercise cycle; resistance means connected to the frame;and an interconnection mechanism interconnecting the resistance meanswith the lever arm at an interconnection point spaced from the pivotaxis, the interconnection mechanism including movement means movable inresponse to a pivotal movement of the lever arm to vary the point ofinterconnection between the resistance means and the lever arm along thelength of the lever arm and guide means interconnected with the frame todefine the path of movement of the movement means so that during aportion of the exercise cycle the interconnection point moves closer tothe handle means as the lever arm pivots about the axis during a firstportion of an exercise cycle and moves farther away from the handlemeans as the lever arm pivots about the axis during a second portion ofthe exercise cycle; whereby, during an exercise cycle, the user issubjected to decreasing and incrasing mechanical advantages and acorresponding increase and decrease in the resistance from theresistance means at the handle means during portions of the exercisecycle. .Iaddend..Iadd.
 16. A device according to claim 15 wherein theforce applying means is disposed intermediate the pivot axis and thehandle means so that mechanical advantage decreases and the resistancefrom the resistance means at the handle means increases during the firstportion of the exercise cycle. .Iaddend. .Iadd.
 17. An exercise devicecomprising: a frame, means defining a pivot in the frame, upright postmeans mounted to the frame and horizontally spaced from the pivot; alever arm having a first end attached to the pivot for pivotal motionrelative to the frame about an axis of the pivot, the pivot axis beingfixed relative to the frame and the lever arm, the lever arm furthercomprising a second end spaced from the pivot and defining handle means,the handle means being disposed on the side of the post means oppositefrom the pivot axis; a weight interconnected with the post means formovement therealong; a mechanism connected with the weight and engagingthe lever arm at an interconnecting point located intermediate thehandle means and the pivot axis where a load generated by the weight isapplied to the lever arm, the mechanism including movement means movablerelative to the lever arm along a portion of the length thereof to varythe interconnecting point between the weight and the lever arm and tothereby move the load relative to the lever arm along a portion of thelength thereof in response to a pivotal motion of the lever arm; andmeans interconnected with the frame for guiding the mechanism along thepost means; whereby the application of a force to the handle means topivot the lever arm about the pivot axis in opposition to the load froma first position to a second position causes a relative movement of themechanism along the lever arm and moves the load along the lever armcloser to the handle means so that the force that must be applied to thehandle means to overcome the load must be correspondingly increased..Iaddend. .Iadd.
 18. A device according to claim 17 wherein themechanism includes low friction means engaging the post means formovement therealong. .Iaddend..Iadd.
 19. A device according to claim 17wherein the mechanism includes a roller engaging the lever arm at theforce applying point and movable along the lever arm when it is pivotedabout the pivot axis. .Iaddend..Iadd.
 20. A device according to claim 17including a plurality of independent weights movable along the postmeans, and including means for varying the number of weights connectedto the mechanism. .Iaddend. .Iadd.
 21. An exercise device comprising: aframe defining a base, upright post means and a pivot shaft having asubstantially horizontal pivot axis attached to the frame andhorizontally spaced from the post means; a lever arm mounted in theframe and engaging the pivot for pivotal movement about the pivot axis,the lever arm being fixed against longitudinal movement with respect tothe pivot axis, the lever arm extending in a direction transverse to thepost means from the axis past the post means and terminating in handlemeans disposed on a side of the post means opposite the pivot axis; aweight movable along the post means; a mechanism for connecting theweight to the lever arm and including means movably mounting themechanism for movement relative to the frame parallel to the post means,the mechanism including movement means engaging the lever arm andapplying the weight to the lever arm at a point located intermediate thepivot axis and the handle means, the movement means including meanspermitting relative motion between the lever arm and the mechanism forshifting the location of the point along the lever arm when the leverarm pivots about the axis; and guide means interconnected with the frameand disposed to direct the path of movement of the mechanism; so that auser can pivot the handle means and the lever arm about the pivot axisbetween a first position and a second position during an exercisingcycle by applying a corresponding exercise force to the handle means,the pivotal movement of the lever arm resulting in an increase of theexercise force during one portion of the exercising cycle and acorresponding decrease of the exercise force during a second portion ofthe exercising cycle to move the weight along the post means. .Iaddend..Iadd.
 22. An exercise device comprising: a frame; a lever arm pivotallymovably mounted in said frame at a lever arm pivot, which is fixedrelative to the frame and lever arm, for movement of the lever arm by auser through an exercise cycle; user contact means interconnected withsaid lever arm for applying pivotal movement force thereto; resistancemeans interconnected with said frame; and an interconnection mechanisminterconnecting said resistance means to said lever arm at a lever armconnecting point disposed in spaced relation with said lever arm pivot,said interconnection mechanism having movement means movable in responseto pivotal movement of said lever arm to vary the spaced relationshipbetween said lever arm connecting point and said lever arm pivot;wherein said interconnection mechanism movement means includes a yokeconnected to said resistance means and disposed about a portion of saidlever arm, and a yoke roller interconnected with said yoke and disposedto travel longitudinally along said lever arm during pivotal movementthereof; and guide means interconnected with said frame and disposed todirect the path of movement of said movement means. .Iaddend. .Iadd. 23.An exercise device comprising: a frame; a lever arm pivotally mounted insaid frame at a lever arm pivot and pivotally movable about the pivot bya user through an exercise cycle, the lever arm being fixed againstlongitudinal movement with respect to the pivot; user contact meansinterconnected with said lever arm for applying pivotal movement forcethereto; resistance means interconnected with said frame, and aninterconnection mechanism interconnecting said resistance means to saidlever arm at a lever arm connecting point disposed in spacedrelationship with said lever arm pivot, said interconnection mechansimhaving movement means movable in response to pivotal movement of saidlever arm to vary the spaced relationship between said lever armconnecting point and said lever arm pivot to correspondingly vary thepoint of interconnection between said resistance means and said leverarm, and guide means interconnected with said frame and disposed todirect the path of movement of said movement means. .Iaddend.